1. Field of the Invention
This invention relates to devices for protecting against the accidental loss and subsequent misuse of valuable cards, such as credit cards, bank cards, telephone calling cards, etc., and in particular, to devices that give a warning that a credit card has not been returned after use, or that an incorrect card has been returned, or that require a password to be used prior to an authorized use of a card.
2. Description of the Related Art
Many people today carry in their wallets or purses several cards, such as credit cards, telephone calling cards, driver's licenses, membership cards, etc. It is often convenient to hold all of these cards in one dedicated credit card wallet or carrier. Sometimes these carriers are thin enough that they can be in the form of an insert to be put into an ordinary wallet. When a person wishes to use a credit card, such as in a restaurant, it is normally removed from the carrier or wallet, handed to a server, and the carrier or wallet is put into a purse or pocket until the card is returned.
It often happens that the card is not returned to the user, or perhaps some other person's card is returned, and this is not noticed by the user, who then leaves the business establishment. It may be several days or longer before it is discovered that the card is missing. Sometimes the user cannot remember where the card was left. The user can notify the card issuer of the lost card, but by the time this happens, the card could get into the hands of someone who may use the card fraudulently and the owner of the card normally is responsible for all charges until the card issuer is notified of the loss of the card. Also, a missing card represents an administrative burden and possibly also a financial loss to the card issuer or financial institution issuing the card.
In order to overcome this problem, several card carriers have been invented with a built-in alarm. The alarm is activated by one or more switches that are actuated by the removal of a credit card from the card carrier. A master switch disables the alarm while the card carrier is out in the open, but if a person tries to put the card carrier back into a pocket or purse without the card being returned, the alarm is activated. An example of such a card carrier is shown in U.S. Pat. No. 4,692,745 issued to Solly Simanowitz. The difficulty with this device, however, is that a person cannot put the card carrier away in a pocket or purse while waiting for the card to be returned. Also, the device cannot determine if an incorrect card is returned to the carrier, nor can password protection be implemented in such devices.
Another type of credit card monitor is shown in U.S. Pat. No. 3,959,789 issued to Francis M. McGahee. The device in this patent also has an alarm, but the alarm is activated by a timer which is energized by the closure of a switch upon the removal of a credit card. This device also has the drawback that it cannot determine if an incorrect card has been returned to the carrier. It also cannot provide password protection in connection with the use of the cards.